Howto debug Kernel problems ? (jail -r -> freeze)

[Denny Schierz]

hi,

Am 24.01.2012 um 21:21 schrieb Marius Strobl:

> On Mon, Jan 23, 2012 at 01:16:22PM +0100, Denny Schierz wrote:
>> hi,
>> 
>> If I stop a jail (v2 with vnet), the jail doesn't completely disappear. "jls" shows the jail as active. If I try to remove the jail with "jail -r <id>" the whole machine freezes. Other users with same options (i386) doesn't have this problem. So how can I debug it?
>> 
> 
> I'd start with a kernel built with BREAK_TO_DEBUGGER, DDB and KDB
> enabled. Then when it appears to hang try to break into the debugger
> by sending a break on the serial console. If that works try to bug
> virtualization@ and probably bz@ directly for information they
> want as given that you mention vnet it sounds like you're not
> seeing this problem without VIMAGE.


hmm, all debug  options are active and  I send the break signal from ALOM, but I think, that FreeBSD isn't configured to interpret the signal. Can I enter the kdb first (sysctl debug.kdb.enter=1) and than execute "jail -r 1" ?

cu denny